Means for sealing pipe leaks



July 27, 1943. P. D. MERRILL ETAL MEANS FOR SEALING PIPE LEAKS FiledOct. 23, 1940' 2 v k w e H Q 7 Wm 5 m/ g V m WWW ATTORNEYfi.

Patented July 27, 1943 UNITED- STATES PATE oF'ricE Patterson D. Merrilland Frederick R. McMurray, 1

South Bend, Ind., assignors to M. B. Skinner Company, South Bend, Ind acorporation of Indiana Application october 23, 1940, Serial No. 352322:

6 Claims.

' This invention relates to means for sealing pipe leaks, and moreparticularly for sealing a leaking pipe by welding thereto a metal patchplate covering the leaking area thereof. The invention is primarilyintended for application to pipes containing fluids suchas natural gas,illuminating gas, or oil, under high pressures.

Various methods. for sealing pipe leaks have been available heretofore.Under one method a sealing element carried by a clamp is compressedagainst and permanently secured on the pipe by said clamp for thepurpose of sealing the leak. This is' quite expensive by reason of thenecessity of permanent retention of not only. the sealing element, butalso a retaining clamp, upon the pipe at each leaking area. Anothermethod has been to apply to a leaking pipe a permanent metal patch platewhich is welded to the pipe. This later method has heretofore hadthedisadvantage of requiring an interruption in pipe service during theinterval required to weld said plate tothepipe. I

Another disadvantages which has been experienced frequently in welding apatch plate isthat it is usually necessary'to apply the welding patch tothe leaking pipe by m'eans of a clamp of a size which is suitable i'oruse only with pipes of a certain predetermined narrow range of sizes.

Hence, it has previously been necessary for a repair crew to carry withit; a supply of clamps of various sizes in order that any pipe in whicha leak develops may be promptly and effectively sealed and patched. 1 j1 The primary object of this invention is to provide means for clampingpatch means to a pipe with an adaptor accommodating clamping of pipes ofa wide range of sizes. N

A further object is to provide an adaptor for a patch clamp having apair of spaced abutment members wherein said' members are adapted eitherto directly engage a pipe or to support the adaptor. 1

A further objectis to provide a pipe-engaging adaptor havinga pair ofspaced ribs projecting from each of two diiferent sides thereof,wherein.

the ribs on one side are of greater height and narrower spacing than theother ribs. y l

A further object is to provide a device of this character havingpressure applying means including an element normally engaging a pipe,and an adaptor selectively mounted upon said element in either oftwo'positions, and having pipe-engaging ribs projectingfrom each of twofaces thereof, and means for securing said adaptor to said elementindependently of said ribs.

Other objects will be apparent from the description, drawing; andappended claims.

In the drawing: f

Fig. 1 "is a view illustrating a leaking pipe in cross section andhaving the improved leak sealing device applied thereto. y

Fig. 2 is a fragmentarylview similar to Fig. 1, and illustrates themanner in which an adaptor may be utilized therewithl p Fig. 3 is anenlarged transverse sectional view of the adaptor taken on line 3 3 ofFig; 4.

Fig. 4 is an enlargedtransverse sectional View of the adaptor taken online 4-4 of Fig. .3.

Fig. 5 is an. enlarged transverse sectional view of a Weld patch platemounting the improved leak sealing gasket.

Fig. 6 is a view similar to Fig. 5, and illustrates a slightly differentconstruction of welding patch plate. 1 I

Referring to the drawing; which illustrates the preferred embo'dimentoithis'invention, the numeral l0 designates a pipehaving a leaking area lltherein. A weldpatch' plate l2 formed of metal, such as anr iron castingor the like, is adapted toibe applied over the leaking area ll of thepipe and to be welded to the pipe at its margin or perimeter. Plate I2is transversely curved in arcuate form to seat snugly on the outersurface of the pipe it, andlcarries a projection l3 at the center of itsconvex face, for purposes to be hereinafter set forth. 7

A gasket i4 is carried bythe inner or concave face of the patch platel2. The gasket I4 preferably constitutes a sheet of compressed andcompacted asbestos fibers which are bonded together in sheet or'web formwithout the use of starch or'other adhesive. The material is normallypenetrable by gases and liquids, and is preferably highly absorbent sothat when wetted wih water. it will readily absorb the water.

The patch plate i2 is ad'apted'to be applied to the pipe It] by means ofclamp !5. This clamp comprises apair of elongatedniembers l6 and l Leachprovided with an inwardlydirected projection l3 intermediate its ends.Suitable pivot means l9 serves to pivotally interconnect the projections58. Members l6 and l! are curved so that the outer ends thereof areclose spaced, while the opposite or clamping'j'aw ends thereof arecomparatively Widely spaced. The first mentioned end of onepfthemembers. such as member l6, has pivctally interconnected thereto, bya pivot pin 28; an elongated lever 22! having cam head 22 whose outersurface is curved eccentrically of the pivot pin 20. JIfhe oppositeclamp member is provided with a bearing face 23 which is inwardly offsettherefrom and against which the cam element 22 may bear.

One of the jaw portions of the clamp terminates in an anvil 24 having arecess 25 in the inner end thereof for loosely receiving the pro jectionL3 of the patchzplate-ll Opposite walls.

I of the recessed -portion .of the .amdlare apertured in register withaperture 26 formed in the projection l3, whereby the patch plate 12 maybe secured within the recess of the anvil for limited swinging movement.The apertures, including aperture 26 are so disposedas.to -l-iesubstantially parallel to the axis of the pipeto which'the same is to beapplied, whereby swingingemovementof,

the jaw [6 to different angular positions will not interfere with properand fulLseating of the plateshown) jf npurposes to, be hereinafter. set"forth.

i Theretorait-willbe.observdd'that in normal use .and-operationiof the.device, a pa h pl i z isfirstconne teidwith the anvil'zfl of a clamp.by means of acotter pin (notshovvn), or other suitable detachableconnecting 1 means.

The .clarnpis ai plied;to .p,iliejlffl with theflanges 2i bearing uponthe pipe at points thereof opposite the leakin narea ,ll .of. the pipe,and with the gasket and .plate 12 substantially centered .1 v and. Sfitinthe'ileaking ,area .of'the pipe. The jaws oftheclampiarelthen urgedinthe die ti n of eachlother by'.. ;p6mtl0n,ofthelever .t h. f..-.camf22 opon'bearing 'fac'elii. i'After thePlalieIFZhaS-I been weldedto.t.he.pip.e around t n ramargin; theplampmayhe disconnectedherefromlqy. releasingilever .2 I and detaching the cottenpinpr other.clamp-,carriedsecuring m ans pass ng pthroughplate. aperture .26.

-It will be observed thattheclampldis of such construction andcharactenflby reason .of the use f am tithcreof for pressure app yin pposes, that it will accommodate v.itself to pipes of onlyarestrictedrange of sizes; Therefore, if the clamp is'tobe operativeioruse with pipes of other sizes, it is necessar .to ,use an adaptortherewith. An adaptor \ifljor this purpose is illustratedingFigs. :3 and.14. -.This adaptor cornprises .a unitary member, preferably .a casting,having a .bodymember comprising .parallel,"

pa ed, opposed. normall horizontal Walls 3 a, narrow opposite end .walls3.2, and. a. central stud portion .33 extending between .the .wallstl,all

formed integrally. Bortion 33-is providedwith a central screw -threadedbore -3.4, forpurposes to be hereinafter set ;forth. "A pair of lugs (tprojectfromopposite ends ;of each of thetwo vertical walls ijlinlaterally outwardly directed relation thereto. The ilugs -at one side ofthe device are provided withalignedgrooves 36 parallel to walls .32sineach of the upper-and lower faces thereof; while*thexupper and lowerfaces tlof the oppositeilug'fi are flat and'lie'in parallel planes-whicha-re'respectivelyintersected Y flanges 27 of 'said clamp element.

the lowermost or innermost portions of the grooves 36. Each of the facesor walls M has projecting therefrom at opposite sides thereof a set oflongitudinally aligned, spaced rib portions. The rib portions 38projecting from one face thereof are spaced apart a dimension lessand-areof greater height t-han'the" ribs 38 projecting'from theopposi-t'ezface or wall.

As best illustrated in Fig. 2, the adaptor 3i] may be mounted upon thejaw ll of the clamp 55 With the lugs thereof supported upon the One ofthe flanges 21 extends into the set of grooves 36 in onefaceofxonje-setoflugs 35, and the other flange 227 engages .themther setof lugs at one of the plane faces:.3.7.1.-thereof. When the adaptor isproperly positioned upon the clamp, a securing member, such as a bolt46, is passed through the. bore of portion 28 of the clamp part i! andis threaded into the bore 3 of .the adaptor to fixedlysecure the adaptortothe clamp. The

ribs 13% are pos'itionedxupwar'clly or inwardly when the-adaptor is' sosecured, whereby the'pipe ldinay rest thereon. Bothysets' of ribs 38 andor the adaptor are spa'ce'd'apart a distance "less than thespacingofflanges 2'! of the clamp.

This factor, together 'Wlth'fthe respective xiiiferentheights ofp' saidribs ari'dthe support of 'the'adaptor at -lugs 35,;accommodatesselective positioningof'the' adaptor in a" manner to support, engage,andclamp' pipes of two different size ranges. For example, assuming that.the

clamp fi 5 is adapted ,to clamp pipeswhose diam- A eter is approximatelyfourinchesjthe adapter 33 may-bepla-ced nponthe clamp as illustrated inFig. 2 for-the purpose of "accommodating and clamping itself' to' pipesofiapproximately I three inch diameter, or maybe reversed fromthe-position illustratedlind 'ig.2,"whereby the ribsSB are uppermost andare -adapted tolaccommodate pipes of approximately two-inch diameter.

It will be obvious that the use .of adaptorSt involvesachange-inthe'relation of the axis of the pipe -being '-clampe'd,"wi'th respect toboth anvil24 and clamp pivot 19; However, the pivotal mounting of" thepatch .plate relative to anvil 24 at -apertur'e26 accommodates'suchchange in --relation oft-he parts, gandthereby insures snug seating ofthe patch'plate .on'the pipe and application of "sealing*pressurextdtheplate'by the c i p- Y The "use of the "asbestos'gasket I successfullyseals the leak Ilin pipe lfl'iduringthe welding operation, and thereby"eliminates any necessity "for interruption of pipe service during thewelding operation; Asbestos is not generally feasible for leak sealingpurposesaandthe instant gasket formed therefrom is .iluid-pervious asabove described. In the instant case this very property 'ofperviousnessisutilized" to create a seal. Thus,

the gasket-is wetted with water before being applied to the pipe, andwhen pressure isapplied to the =wettedgasket by .or through the patchplate, the gasketserves "to eifectivelyseal the pipe "leak; This resultcan be achieved eifectively -only when the fibrous asbestos used in thegasket has not been bound by starch or other adhesives which wouldtendto reduce gasket absorbency.

yWliile-the exact reason 'for the effectiveness of thewetted'absorbent'asbestos gasket as a. sealing :element isnot known, it.appears that the absorptionof water thereby. tends to soften the fibersso that theymay be so firmly compacted "by-pressure appliedby the plateas to assume the properties of a homogenous body having a flexibilitysufficient to permit an intimate engagement thereof with the pipe. Inany event, it has been found that the wetted asbestos gasket will sealthe pipe leak effectively, even against high pressure leaking gas, andwill maintain the seal during the entire time required to weld themargin of patch plate 12 by the use of an acetylene torch generatingheat sufficient to causefailure of all gasket materials heretoforetested.

If desired, the plate l2 may have its margin slightly offset as shown inFig. 6. This construction forms a pocket for the gasket effective toretain the gasket when the pipe carries fluids at very high pressures,and has the additional advantage of positioning the plate margin closeto the pipe to facilitate welding.

I claim:

. for engaging pipes of a predetermined limited 1. In a pipe leaksealing deviceincluding a 7 pair of clamp elements adapted to applypressure against opposite sides of a pipe, an adaptor, means forsecuring said adaptor to one of said elements, said adaptor having apair of parallel pipe-engaging ribs projecting from each of two opposedfaces thereof, and element-engaging adaptor faces laterally outwardlyoff-set from the bases of said ribs, the ribs at one face of said memberbeing spaced apart a distance greater than and projecting from saidelement a shorter distance than the ribs at the opposite face of saidmember.

2. An adaptor for a pipe clamp having a pressure applying memberprovided with a pair of parallel projections, comprising a body portionadapted to seat on said projections and a, pair of spaced parallel ribsprojecting from intermediate portions of each of two opposed sides ofsaid body portion and both spaced closer than said clamp projections,the ribs of one of said pairs being of a different height and spacingthan the ribs of the other pair.

3. An adaptor as defined in claim 2 wherein size range, of a shallowadaptor having a pair of ribs projecting from each of two opposed facesthereof, one set of adaptor ribs being spaced apart a distance greaterand projecting from said adaptor a distanc less than the other set ofribs, said adaptor bearing on said clamp ribs outwardly of said adaptorribs and means for securing said adaptor to said ribbed clamp elementspaced from said ribs, said adaptor accommodating selective gripping bysaid clamp of pipes of either of two different size ranges smaller thansaid first mentioned range.

6. A pipe-engaging adaptor comprising a narlow body portion having acentral transverse screw-threaded bore, two sets of longitudinallyspaced aligned ribs projecting from each of two opposite faces of saidbody portion, wings projecting laterally from said body portionoutwardly of said ribs, one of said wings being grooved parallel to saidribs and the other having a plane supporting face, the ribs projectingfrom one face of said body member being spaced apart and of a heightdifferent from the spacing and height of the ribs at the opposite faceof said body member.

PATTERSON D. MERRILL. FREDERICK R. MCMURRAY.

